Squandering riches: can Perth realise the value of its biodiversity?

Perth is not known as a model for suburbia and its suburban condition is similar to that of developed cities the world over. However, it does stand out in one respect: it sits in an exceptionally biodiverse natural setting. A strong, informed vision for this setting’s relationship with the city could help Perth become an exemplar for similarly positioned metropolises everywhere.

The greater Perth region has been designated the Southwest Australia Ecoregion (SWAE). This is one of only 35 “biodiversity hotspots” in the world.

Reconciling future growth with biodiversity is a key issue for urban design and planning this century. Indeed, if current trends continue, global urban land cover will increase by 1.2 million square kilometres (equivalent to half the area of Western Australia) by 2030. Much of this will happen in biodiversity hotspots.

This is important because it is estimated we will lose nearly half of all terrestrial species if we fail to protect the hotspots. We will also lose the ecosystem services upon which human populations ultimately depend.

Perth has a reputedly strong planning system and is comparatively wealthy. If it can’t control its city form to protect biodiversity – compact cities generally being recognised as the best model for protecting land for conservation – then city administrators elsewhere, particularly in the developing world, are likely to struggle.

Perth’s Green Growth Plan

The release of the state government’s long-anticipated Perth and Peel Green Growth Plan for 3.5 million may herald a shift in the relationship between the city and the biodiversity hotspot. The plan encapsulates two broad goals:

to protect fringe bushland, rivers, wetlands and wildlife in an impressive 170,000 hectares of new and expanded reserves on Perth’s fringe

While ostensibly positive achievements, a question remains as to the implications of clearing a further 45,000ha (3% of the Swan Coastal Plain) of remnant bushland which is not protected by the conservation reserves.

Furthermore, the typically disconnected conservation reserves proposed in the Green Growth Plan lack overall legibility. This stymies the public’s ability to conceptualise the city’s edge, which leads them to care about it (like London’s greenbelt, for instance).

Finally, a question remains about how a plan that places restrictions on outer suburban development will accommodate the powerful local land development industry over time. This is a concern given the frequent “urban break-outs” – where urban development occurs outside nominated growth areas – between 1970 and 2005.

In 2003, the ABC asked revered Western Australian landscape architect Marion Blackwell, “Are we at home now in the land we live in?” She replied, “No, we’re not. We don’t know enough about it, and not enough people know anything about it.”

We still have work to do on our engagement with biodiversity in Western Australia, and Perth specifically, before we can become a model for future cities.